Article Sorting Facility

ABSTRACT

An article sorting facility includes a plurality of storage members each configured to store one or more articles, a plurality of article transport vehicles each capable of traveling in at least a portion of a preset travel lane with one or more support members on board, each support member being configured to support one or more articles; a plurality of work areas each configured to allow work to be performed to transfer articles between one or more storage members and at least one of the one or more support members on board an article transport vehicle in the travel lane, wherein each of the work areas is located adjacent to one or more storage members and to the travel lane, wherein the plurality of work areas are arranged one adjacent to another along the travel lane, and wherein two or more article transport vehicles are in the travel lane simultaneously to travel in a line.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority to Japanese Patent Application No.2018-133521 filed Jul. 13, 2018, the disclosure of which is herebyincorporated by reference in its entirety.

FIELD OF THE INVENTION

The present invention relates to an article sorting facility whichcomprises a plurality of storage members each configured to store one ormore articles, and a plurality of work areas each configured to allowwork to be performed to transfer articles.

BACKGROUND

An example of such a conventional article sorting facility is describedin JP Publication of Application No. 2011-246234 (Patent Document 1). Inthe article sorting facility of Patent Document 1, a worker is locatedin each of a plurality of work areas and a conveyor (first straightforward transporting line 21A) which extends along the plurality of workareas is installed for transporting article collecting containers(article collecting containers 10). The worker in each work areaperforms transfer work in which the worker removes articles from one ormore storage members and placed them in article collecting containers.

SUMMARY OF THE INVENTION

With the article sorting facility described above, transporting of allarticle collecting containers stops if a conveyor is stopped becausetransfer work took too much time in a specific work area, for example.Since this may lead to a situation in which transfer work in other workareas have to be interrupted, such situation may reduce the efficiencyof the transfer work in each work area. In addition, for example,article collecting containers are transported one after another alongthe entire length of the conveyor. Thus, when working in a work area,all the article collecting containers are transported one after another(including ones that are not used in the particular work area) on aportion of the conveyor that corresponds to the work area. Thus, theefficiency in transporting article collecting containers that are usedin transfer work is reduced by the amount that corresponds to the numberof article collecting containers that are being transported but not usedin the transfer work in certain work areas, which in turn reducesefficiency of transfer work in work areas. Thus, with the articlesorting facility described above, there is room for improvement toimprove the work efficiency in work areas.

Thus, an article sorting facility is desired which can further improvework efficiency in the work areas.

An article sorting facility in accordance with the present disclosurecomprises: a plurality of storage members, each configured to store oneor more articles; a plurality of article transport vehicles each capableof traveling in at least a portion of a preset travel lane with one ormore support members on board, each support member being configured tosupport one or more articles; a plurality of work areas each configuredto allow work to be performed to transfer articles between one or morestorage members and at least one of the one or more support members onboard an article transport vehicle in the travel lane, wherein each ofthe work areas is located adjacent to one or more storage members and tothe travel lane, wherein the plurality of work areas are arranged oneadjacent to another along the travel lane, and wherein two or morearticle transport vehicles are in the travel lane simultaneously totravel in a line.

With such an arrangement, articles are transported by article transportvehicles, with the articles supported by the support members, after thearticles are transferred to the article transport vehicles in the travellane. Therefore, even when, for example, an article transport vehicle towhich articles are transferred is caused to stop traveling because ofthe transfer work taking too much time in a particular work area,another article transport vehicle traveling ahead of the stopped articletransport vehicle, or another article transport vehicle travelingbehind, and with some distance from, the stopped article transportvehicle can continue traveling without stopping. Therefore, workers inother work areas can continue with their transfer work to transferarticles to the article transport vehicles. Thus, the arrangement abovehelps reduce the lowering of efficiency of transfer work in other workareas caused by transfer work taking too much time in one or more workareas. In addition, by causing any article transport vehicle, to whichall required articles have been transferred, to move out of the travellane, the ratio of the article transport vehicles in the travel lane, towhich articles need to be transferred, to the article transport vehiclesin the travel lane, to which no more articles need to be transferred,can be increased. Such an arrangement helps improve work efficiency inthe work areas.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a plan view of an article sorting facility of a firstembodiment,

FIG. 2 is an enlarged plan view of a portion of the article sortingfacility of the first embodiment,

FIG. 3 is a side view of the article sorting facility of the firstembodiment,

FIG. 4 is a control block diagram for the first embodiment,

FIG. 5 shows how an article transport vehicle in the first embodimentchanges lanes,

FIG. 6 is a plan view of an article transport vehicle showing bothbefore and after rotating support members in the first embodiment,

FIG. 7 shows how an article transport vehicle in the first embodimentchanges lanes to the travel lane,

FIG. 8 is a side view of an article sorting facility of the secondembodiment,

FIG. 9 is a plan view of the article sorting facility of the secondembodiment,

FIG. 10 is a plan view of an article sorting facility of the thirdembodiment,

FIG. 11 is a side view of the article sorting facility of the thirdembodiment, and

FIG. 12 shows a temporary storage station of the third embodiment beforeand after it causes a support member to support an article.

DETAILED DESCRIPTION OF EMBODIMENTS 1. First Embodiment

The first embodiment of an article sorting facility is described withreference to the drawings. As shown in FIG. 1, an article sortingfacility of the present embodiment comprises article storage racks 2having a plurality of storage members 1 each configured to storearticles W, a plurality of article transport vehicles 4 each capable oftraveling in at least a portion of a preset travel lane L1 with supportmembers 3 on board with each support member 3 being configured tosupport one or more articles W, and a plurality of work areas E1 eachconfigured to allow work to be performed to transfer articles W betweenstorage members 1 and the support members 3 of an article transportvehicle 4 in the travel lane L1. In the present embodiment, workperformed in each work area E1 is “picking” in which a worker transfersarticles W from storage members 1 to the support members 3 of articletransport vehicles 4 in the travel lane L1. In addition, the articlesorting facility further comprises a controller H (see FIG. 4) which isconfigured to manage (for example, keeps and update records of thekinds, locations, and the number, and other information, of) thearticles W stored in the article storage racks 2, and to control thearticle transport vehicles 4, among other things. Each controller in thepresent embodiment (such as the controller H and the vehicle controller20) has a CPU, memory circuitry, and communication circuitry tointerface with other relevant components such as sensors, and/oractuators through wires or wirelessly, as well as algorithms in the formof computer code stored in memory and executable by the CPU to performrequired functions.

A transfer area E2 is provided at a location downstream of the travellane L1 with respect to the travel direction of the article transportvehicles 4. Two or more article transport vehicles 4 are in the travellane L1 simultaneously to travel in a line. In the transfer area E2 incontrast, the article transport vehicles 4 travel without restrictionsin terms of their travel directions or travel paths. The transfer areaE2 is an area in which a plurality of article transport vehicles 4 areallowed to travel without being in a line and without being required tomaintain the traveling order (i.e., an article transport vehicle 4traveling behind another is allowed to move ahead of the another). Agreater number of article transport vehicles 4 than the number of thework areas E1 travel in the travel lane L1 simultaneously. And aplurality of article transport vehicles 4 travel such that there are oneor more article transport vehicles 4 in each of the plurality of laneareas LE (see FIG. 2). It is preferable that a greater number of articletransport vehicles 4 than the number of the work areas E1 travel in thetravel lane L1 at any one time. For example, it is preferable that twiceas many, or more, of article transport vehicles 4 as the work areas E1be arranged to travel in the travel lane L1 at any one time.

In addition to the travel lane L1, the article sorting facility isprovided with a branch lane L2 and a completed lane L3 each of whichallows an article transport vehicle to travel in parallel to anotherarticle transport vehicle 4 that is traveling in the travel lane L1. Thebranch lane L2 and the completed lane L3 are disposed to extend parallelto the travel lane L1. A plurality of article transport vehicles 4travel in the same direction in the travel lane L1, the branch lane L2,and the completed lane L3. As shown in FIG. 2, the travel lane L1 hasthe lane areas LE that correspond in location to the work areas E1 witheach lane area LE corresponding to a work area E1.

As shown in FIG. 1, the downstream side end portions of the travel laneL1, the branch lane L2, and the completed lane L3 are all connected tothe transfer area E2. In addition, the upstream side end portion of areturn lane L4 is connected to the transfer area E2. The downstream sideend portion of the return lane L4 is connected to the upstream side endportions of the travel lane L1 and the branch lane L2. Each articletransport vehicles 4 enters the transfer area E2 from the downstreamside end portion of the travel lane L1, the branch lane L2, or thecompleted lane L3, and enters the upstream side end portion of thereturn lane L4 from the transfer area E2. In addition, each articletransport vehicle 4 enters the upstream side end portion of the travellane L1 or the branch lane L2 from the downstream side end portion ofthe return lane L4. Thus, looped paths along which the article transportvehicles 4 travel are formed by the three lanes (the travel lane L1, thebranch lane L2, the completed lane L3), the transfer area E2, and thereturn lane L4.

A container supplying station 6 from which each article transportvehicle 4 receives containers C is provided at or adjacent to thedownstream side end portion of the return lane L4. And a containerreceiving station 7 to which the containers C are delivered from eacharticle transport vehicle 4 is provided at or adjacent to the upstreamside end portion of the return lane L4. The article transport vehicles 4receive empty containers C (in which no articles W are held) from thecontainer supplying station 6. Articles W are placed in containers C byworkers M while the article transport vehicles 4 are traveling in thetravel lane L1. The article transport vehicles 4 deliver the containersC with articles W held within to the container receiving station 7. Inthe present embodiment, the support members 3 on each article transportvehicle 4 are the two containers C received from the container supplyingstation 6.

The article sorting facility is described in greater detail next. Asshown in FIG. 2, in the following description, a direction parallel tothe travel lane L1 will be referred to as the first direction X with afirst side X1 along the first direction X being the downstream side(forward side) of the travel direction when an article transport vehicle4 is traveling parallel to the travel lane L1 and with a second side X2along the first direction X being the side opposite from the first sideX1. In addition, a direction perpendicular to the first direction X in atop-down view along the vertical direction Z will be referred to as asecond direction Y with a first side Y1 along the second direction Y isthe side along the second direction Y on which an article storage rack 2is located with respect to the corresponding work area E1 and with asecond side Y2 along the second direction Y being the side opposite fromthe second side X1. Note that, in the present embodiment, the first sideY1 along the second direction Y is the work side on which an work areaE1 is located with respect to the travel lane L1.

The branch lane L2 is formed to be located adjacent to, and to thesecond side Y2 along the second direction Y of, the travel lane L1. Thecompleted lane L3 is formed to be located adjacent to, and to the secondside Y2 along the second direction Y of, the branch lane L2. A pluralityof work areas E1 are formed to be located adjacent to, and to the firstside Y1 along the second direction Y of, the travel lane L1. A pluralityof article storage racks 2 are located adjacent to, and to the firstside Y1 along the second direction Y of, the plurality of work areas E1.The travel lane L1, the branch lane L2, the completed lane L3, and a rowof the plurality of work areas E1 are formed to extend parallel to thefirst direction X. In addition, the plurality of article storage racks 2are installed to form a row parallel to the first direction X.

As shown in FIG. 3, each article storage rack 2 has a plurality ofstorage members 1 arranged one above another along the verticaldirection Z with each storage member 1 being configured to storearticles W. In the present example, each storage member 1 is tilteddownward toward its end on the second side Y2 along the second directionY such that an article W placed on the storage member's portion on thefirst side Y1 along the second direction Y would slide down the storagemember 1 under its own weight toward and reach the storage member's endon the second side Y2 along the second direction Y if unobstructed.Therefore, each storage member 1 is a tilted shelf member in the presentexample. Note that, in the present embodiment, the articles W are storedin article storage racks 2 with articles W placed in containers D forstoring purposes (or storage containers D for short).

A plurality of kinds of articles W are stored on a plurality of storagemembers 1 with the same kind of articles W being grouped together. Andeach storage member 1 is used to store one kind of articles W. A display9 is provided at the end portion (of each storage member 1) that is onthe second side Y2 along the second direction Y. Each such display 9 isconfigured to be capable of displaying or providing, among other things,a target storage member indication that indicates that the storagemember 1 it is provided to is the one from which one or more articles Wneed to be removed in picking work, as well as an indication as to thenumber of articles W to be removed from the storage member 1. Eachdisplay 9 is controlled by the controller H (see FIG. 4).

As shown in FIGS. 1 and 2, a plurality of work areas E1 are providedalong the first direction X. Each of the plurality of work areas E1 hasone article storage rack 2 installed to correspond thereto. Each of thework areas E1 is located adjacent to both storage members 1 and thetravel lane L1. And the plurality of work areas E1 are arranged oneadjacent or next to another along, or parallel to, the travel lane L1.

As shown in FIG. 2, a low wall or a low partition 11 which partitionsoff the travel lane L1 from the plurality of work areas E1 is installedbetween the travel lane L1 and the plurality of work areas E1 along thesecond direction Y. In addition, an indicator lamp 12 for indicating thearticle transport vehicle 4 that is the target of picking work (i.earticle transport vehicle 4 to which one or more article W need to betransferred in picking work) is provided to correspond to each of theplurality of work areas E1. Each indicator lamp 12 is located betweenthe corresponding work area E1 and the travel lane L1 and at a locationalong the first direction X that corresponds to a central portion, alongthe first direction X, of the corresponding work area. The indicatorlamp 12 is turned on when the article transport vehicle 4 that is thetarget of picking work is in the corresponding lane area LE. And theindicator lamp 12 is turned off when the article transport vehicle 4that is the target of picking work is not in the corresponding lane areaLE. Each indicator lamp 12 is controlled by the controller H (see FIG.4).

Each of the work areas E1 allows, and has in operation, a worker Massigned thereto to work therein. The worker M in a work area E1performs picking work by retrieving one or more articles W from one ormore storage members 1 that correspond to the work area E1 to which theworker M is assigned, and by placing the one or more articles W in oneor both of the support members 3 of an article transport vehicle 4 inthe lane area LE to which the worker is assigned. The displays 9 allowthe worker to see the location(s) of the storage member(s) from whicharticles W need to be retrieved as well as the number of the articles Wthat need to be retrieved from each storage member 1. In addition, theindicator lamp 12 that is turned on allows the worker to identify thearticle transport vehicle 4 on or in which the articles W picked fromthe storage member(s) 1 need to be placed. An arrangement is preferablymade so that, when two or more article transport vehicles 4 are in alane area LE, a worker can identify which of the article transportvehicles 4 is the one on or in which the articles W need to be placedamong the plurality of article transport vehicles 4, by the differentways the indicator lamp 12 emits light (for example, by emitting lightof different colors or lighting patters for different vehicles, etc.).Alternatively, while not shown, two or more indicator lamps 12 may beinstalled in each work area E1.

The controller H shown in FIG. 4 has stored article information storedtherein which is information on the kinds or types of articles W thatare stored on the storage members 1. When a picking command is outputtedfrom a superordinate controller, the controller H is configured totransmit picking information to an article transport vehicle 4 based onthe picking command and the stored article information. Pickinginformation includes at least one of: (a) information that representsthe lane area LE that corresponds to the work area E1 in which pickingwork needs to be performed, (b) information that represents the positionof the support member 3 (i.e., the first support member 3A or the secondsupport member 3B) to which the article(s) W need to be placed in thepicking work, (c) kind information that represents the kind or type ofarticle(s) W to be placed in the support member 3, and (d) the numberinformation that represents the number of article(s) W to be placed inthe support member 3,

As shown in FIG. 3, each article transport vehicle 4 has a travel member16 which is configured to travel on the floor surface F and to supportsupport members 3. As shown in FIG. 4, the travel member 16 is providedwith a reader device 18 (such as a 2D barcode reader) configured to readin reference position information provided on the floor surface F, aweighing portion 19 (which includes one or more weighing scales)configured to measure the weight of the articles W supported by thesupport members 3, and a vehicle controller 20 configured to control thetravel member 16. Reference position information is information thatindicates reference positions in each lane L1-L4. In the presentembodiment, reference position information is provided bytwo-dimensional codes (such as 2D barcodes) located on the floor surfaceF, and, more specifically, is provided by tags (for example, first tagT1 and second tag T2 shown in FIG. 7) each attached to the floor surfaceF and each having a two-dimensional code printed or otherwise displayedthereon. The reference position information provided by each tag notonly includes information that indicates that the location of the tag isa reference position, but also includes address information whichindicates the location (such as coordinates, or a unique set of numbersassigned to each location, among other possibilities) within the entirepaths traveled by the article transport vehicles 4.

As shown in FIG. 6, the support members 3 include a first support member3A and a second support member 3B, each configured to independentlysupport one or more articles W (the expression “independently supportone or more articles W” means that one or more articles W that aresupported by the first support member 3A are not supported by the secondsupport member 3B and vice versa). The first support member 3A and thesecond support member 3B are located horizontally adjacent to each otherwhen placed on board an article transport vehicle 4. In the presentembodiment, each of the first support member 3A and the second supportmember 3B is a container C and is placed on the travel member 16. Whenone or more support members 3 are placed on, or otherwise supported by,the travel member 16, the one or more support members 3 are said to beon board the article transport vehicle 4; and thus, when that is thecase, the article transport vehicle 4 travels “with the one or moresupport members 3 on board”.

As shown in FIG. 3, the travel member 16 of each article transportvehicle 4 has a pair of travel wheels 22 that are spaced apart from eachother along a direction perpendicular to the travel direction in whichthe article transport vehicle 4 travels, as seen along the verticaldirection Z, a pair of non-driven wheels 23 with one located on one sideand the other located on the other side, along the travel direction, ofthe pair of travel wheels 22 in a side view (see FIG. 12), and actuatorsor drive electric motors 24 (see FIG. 4) each of which drivingly rotatescorresponding one of the travel wheels 22. When an article transportvehicle 4 is traveling straight forward along the first direction X, thepair of travel wheels 22 are spaced apart from each other along thesecond direction Y whereas the non-driven wheels 23 are located one andthe other side, along the first direction X, of the pair of travelwheels 22 in a side view. The travel member 16 travels forward when bothof the pair of travel wheels 22 are rotated in a forward direction bythe drive motors 24 and travels backward when both of the pair of travelwheels 22 are rotated in a reverse direction by the drive motors 24.

In addition, the travel member 16 is configured to be capable ofchanging the speed of the article transport vehicle 4 by changing therotational speed of the travel wheels 22 when rotating both travelwheels 22 in the forward direction with the drive motors 24. And each ofthe article transport vehicles 4 is configured to be capable oftraveling independently of each other and of independently changing itstravel speed. In the present embodiment, each article transport vehicle4 is configured to be capable of traveling at (and thus of changingspeeds from one to any other of) a first speed, a second speed which isgreater than the first speed, and a third speed which is less than thefirst speed. In the present embodiment, the third speed is the speed(i.e., zero) at which the article transport vehicle 4 is at rest.

Each article transport vehicle 4 is capable of changing its direction oftravel while traveling, as a result of one drive motor 24 of the travelmember 16 rotating one of the travel wheels at a rotational speed thatis different from the rotational speed at which the other drive motor 24is rotating the other of the travel wheels. Each article transportvehicle 4 is capable of changing lanes from the travel lane L1 to thebranch lane L2 by changing the direction of travel when traveling in thetravel lane L1, as indicated by the arrow (1) in FIG. 5. In addition,each article transport vehicle 4 is capable of changing lanes from thebranch lane L2 to the travel lane L1 by changing the direction of travelwhen traveling in the branch lane L2, as indicated by the arrow (2) inFIG. 5. Thus, each article transport vehicle 4 is configured to becapable of changing lanes from the travel lane L1 to the branch lane L2and from the branch lane L2 to the travel lane L1. In addition, eacharticle transport vehicle 4 is capable of changing lanes from the travellane L1 to the completed lane L3 by changing the direction of travelwhen traveling in the travel lane L1, as indicated by the arrow (3) inFIG. 5. Thus, each article transport vehicle 4 is configured to becapable of changing lanes from the travel lane L1 to the completed laneL3.

As shown in FIG. 6, the article transport vehicle 4 is configured to becapable of rotating the support members 3 about an axis extending alongthe vertical direction Z. In the travel lane L1, the article transportvehicle 4 is configured to be capable of rotating the support members 3to a first rotational state (state shown on the right hand side in FIG.6) in which the first support member 3A is located on the first side Y1along the second direction Y with respect to the second support member3B and to a second rotational state (state shown on the left hand sidein FIG. 6) in which the second support member 3B is located on the firstside Y1 along the second direction Y with respect to the first supportmember 3A. In the present embodiment, the article transport vehicle 4 isconfigured to rotate the support members 3 to the first rotational stateand to the second rotational state as a result of the travel member 16turning on the vertical axis using the pair of the travel wheels 22.

The vehicle controller 20 performs, based on picking informationtransmitted from the controller H, a travel control for controlling thetravel member 16, and a determining control for determining whetherrequired picking work has been completed. In the travel control, thevehicle controller 20 controls the travel member 16 to cause the articletransport vehicle 4 to travel, in sequence, one or more lane areas LEeach of which corresponds to a work area E1 in which picking work needsto be performed. In the determining control, the vehicle controller 20determines (for each of one or more lane areas LE each corresponding toa work area E1 in which picking work needs to be performed) if therequired picking work that needs to be performed in a working area E1that correspond to the lane area LE has been completed. When referenceposition information is read by the reader device 18 while the travelcontrol is being performed, the article transport vehicle 4 transmitsthe reference position information together with the vehicle's ownidentification code to the controller H. The controller H is configuredto learn the locations of the plurality of article transport vehicles 4based on the identification code and reference position informationtransmitted from the plurality of article transport vehicles 4.

The weight information which indicates the weight of each article W isstored by the vehicle controller 20. The weighing portion 19 isconfigured to be capable of weighing the weight of each of a pluralityof support members 3 individually, or of weighing the weight of theplurality of support members 3 as a whole. In the determining control,the vehicle controller 20 determines whether the exact number (asindicated by the number information) of articles W of each kindindicated by the kind information have been placed in the specifiedsupport member 3, thus whether the required picking work for a givenwork area E1 has been completed, based on changes in the weight measuredby the weighing portion 19, kind information of article(s) W which isprovided in the picking information and which indicates the kind(s) ofarticle(s) W that need be placed in and supported by a support member 3,weight information of each article W of each kind indicated by the kindinformation, and number information for the articles W (the number ofthe articles W of each kind that need to be picked) indicated by thepicking information.

In the travel control, the vehicle controller 20 controls the travelmember 16 of each article transport vehicle 4 to cause the articletransport vehicle 4 to travel only in the lane areas LE in which pickingwork needs to be performed. In addition, the vehicle controller 20controls the travel member 16 of each article transport vehicle 4 tocause the article transport vehicle 4 not to travel in the lane areas LEin which picking work for the article transport vehicle 4 is notperformed, and to cause the article transport vehicle 4 to travel in thebranch lane L2 or the completed lane L3 which is located to the secondside Y2 along the second direction Y of these lane areas LE. Morespecifically, the travel member 16 is controlled in the travel controlas follows.

When picking work needs to be performed in the lane area LE that islocated at the end on the second side X2 along the first direction Xamong the plurality of lane areas LE, an article transport vehicle 4enters the travel lane L1 from the return lane L4 and travels in thetravel lane L1 at the first speed. Also, when no picking work isperformed in the lane area LE that is located at the end on the secondside X1 along the first direction X among the plurality of lane areasLE, an article transport vehicle 4 enters the branch lane L2 from thereturn lane L4 and travels in the branch lane L2 at the second speed.And when an article transport vehicle 4 (first article transport vehicle4) is traveling in any lane and another article transport vehicle 4(second article transport vehicle 4) is traveling directly ahead (i.e.located to the first side X1 along the first direction X in the samelane) at a lower speed than the first article transport vehicle 4, thenthe first article transport vehicle 4 reduces its speed to match thespeed of the second article transport vehicle 4 such that the firstarticle transport vehicle 4 follows the second article transport vehicle4 with a preset distance between the two vehicles 4. Note that, in thepresent embodiment, the present distance is set to be less than thelength of each article transport vehicle 4 along the first direction X.

And when an article transport vehicle 4 is traveling in a lane area LEof the travel lane L1, if it is determined in the determining controlthat picking work has not been completed, then the article transportvehicle 4 travels (or keeps on traveling) in the lane area LE at thefirst speed. And when an article transport vehicle 4 is traveling in alane area LE of the travel lane L1, if it is determined in thedetermining control that picking work has been completed, then thearticle transport vehicle 4 travels in (the remainder of) the lane areaLE at the second speed. As a result of performing the travel control inthis manner, when traveling in a lane area LE, each article transportvehicle 4 travels: (a) at the first speed until all the required pickingwork (that needs to be performed in a work area E1 that corresponds tothe lane area LE) to transfer one or more article W to at least one ofthe support members 3 on board the article transport vehicle 4 iscompleted in the work area E1; and (b) at the second speed (which is ahigher speed than the first speed) after the required picking work totransfer the one or more articles W to the at least one of the supportmembers 3 on board the article transport vehicle 4 has been completed.

And when an article transport vehicle 4 is traveling in a lane area LE,if the article transport vehicle 4 reaches the end of the lane area LEon the first side X1 along the first direction X in spite of the factthat required picking work (that needs to be performed in an work areaE1 that corresponds to the lane area LE) has not been completed, thenthe article transport vehicle 4 reduces its speed to the third speed(i.e. stops). This arrangement prevents an article transport vehicle 4from leaving a lane area LE before the required picking work that needsto be performed in a work area E1 that corresponds to the lane area LEto transfer articles W to at least one of the support members 3 on boardthe article transport vehicle 4 is completed in the work area E1.

When all the required picking work (that need to be performed in thework areas E1 that correspond to all the specified lane areas LE) totransfer articles W to an article transport vehicle 4 has beencompleted, the article transport vehicle 4 changes lanes from the travellane L1 to the completed lane L3, as shown with the arrow (3) in FIG. 5.If and when the article transport vehicle 4 changes lanes to thecompleted lane L3, the article transport vehicle 4 travels in thecompleted lane L3 at the second speed to the transfer area E2.

When required picking work (that needs to be performed in a work area E1that corresponds to a lane area LE) to transfer one or more articles Wto an article transport vehicle 4 has just been completed, and ifpicking work, to transfer one or more articles W to that articletransport vehicle 4, needs to be performed in the next work area E1 thatcorresponds to the next lane area LE that is adjacent, on the first sideX1 along the first direction X, to the lane area LE corresponding to thework area E1 in which the required picking work has just been completed,then the article transport vehicle 4 continues to travel in the travellane L1, as shown with the arrow (4) in FIG. 5, at the second speed. Thearticle transport vehicle 4 travels in the lane area LE in the travellane L1 and reduces its speed to the first speed when it enters the nextlane area LE that is adjacent to the lane area LE.

In addition, when required picking work (that needs to be performed in awork area E1 that corresponds to a lane area LE) to transfer one or morearticles W to an article transport vehicle 4 has just been completed,and if there is no picking work to be performed for the articletransport vehicle 4 in the next work area E1 that corresponds to thelane area LE that is adjacent, on the first side X1 along the firstdirection X, to the lane area LE corresponding to the work area E1 inwhich the required picking work has just been completed, then thearticle transport vehicle 4 changes lanes from the travel lane L1 to thebranch lane L2, as shown with the arrow (1) in FIG. 5. If an articletransport vehicle 4 changes lanes to the branch lane L2, it travels inthe branch lane L2 at the second speed, after which, as shown with thearrow (2) in FIG. 5, the article transport vehicle 4 reduces its speedto the first speed and changes lanes to enter a lane area LE(corresponding to a work area in which the next picking work is to beperformed) through or at the lane area's end portion on the second sideX2 along the first direction X (this end portion will be referred to asa merging location G).

How an article transport vehicle 4 that is traveling in the branch laneL2 changes lanes to the travel lane L1 is described next.

As shown in FIG. 7, a first tag T1 is provided at a reference positionin the travel lane L1 with the reference position being located short ofa corresponding merging location G (i.e., the reference position beingso located that an article transport vehicle 4 traveling in the travellane L1 would reach it before reaching a corresponding merging locationG). The first tag T1 indicates, or otherwise provides, referenceposition information which indicates the location of the first tag T1 aswell as the fact that the location is a reference position. An articletransport vehicle 4 that is traveling in the travel lane L1 and that hasnot yet entered a merging location G is capable of reading the referenceposition information on a first tag T1 by means of the reader device 18.In addition, a second tag T2 is provided at a reference position that islocated in the branch lane L2 and short of a location corresponding,along the first direction X, to the merging location G. The second tagT2 indicates, or otherwise provides, reference position informationwhich indicates the location of the second tag T2 as well as the factthat the location is a reference position. An article transport vehicle4 that is traveling in the branch lane L2 and that has not yet enteredthe location corresponding, along the first direction X, to the merginglocation G is capable of reading the reference position information onthe second tag T2 by means of the reader device 18. In the presentembodiment, the second tag T2 is located to the first side X1 along thefirst direction X of the first tag T1 and is spaced apart from the firsttag T1 by a distance corresponding to the difference DIF between: (a)the distance traveled by an article transport vehicle 4 traveling in thebranch lane L2 up to the point in time the article transport vehicle 4finishes changing lanes to the travel lane L1 and (b) the distancetraveled by an article transport vehicle 4 traveling in the travel laneL1 as it continues traveling in the travel lane L1. In the presentexample, the difference DIF is equal to the distance, along the seconddirection Y, between the center line (along which tags are located) ofthe travel lane L1 and the center line (along which tags are located) ofthe branch lane L2.

When an article transport vehicle 4 traveling in the travel lane L1reads the reference position information on a first tag T1, it transmitsthe vehicle's identification code and the reference position informationto the controller H. When an article transport vehicle 4 traveling inthe branch lane L2 reads the reference position information on a secondtag T2 that corresponds to the merging location G that the articletransport vehicle 4 needs to enter, it transmits merging information, inaddition to the vehicle's identification code and the reference positioninformation, to the controller H. Of an article transport vehicle 4traveling in the travel lane L1 and an article transport vehicle 4traveling in the branch lane L2, the controller H causes the articletransport vehicle 4 that reads the reference position information beforethe other to enter the merging location G before the other.

When causing an article transport vehicle 4 traveling in the travel laneL1 to enter a merging location G, if there is another article transportvehicle 4 that is traveling in the branch lane L2 and that reads thereference position information on the corresponding second tag T2 afterthe article transport vehicle 4 traveling in the travel lane L1 read thereference position information on the corresponding first tag T1 andbefore it passes through the merging location G, then the controller Htransmits merging allowing information (information provided to allowthe lane change) to the article transport vehicle 4 traveling in thebranch lane L2 after the first article transport vehicle 4 traveling inthe travel lane L1 has passed through the merging location G.

When causing an article transport vehicle 4 traveling in the branch laneL2 to enter a merging location G before the other, the controller Htransmits merging allowing information to that article transport vehicle4. Also, when causing an article transport vehicle 4 traveling in thebranch lane L2 to enter a merging location G, if there is anotherarticle transport vehicle 4 that is traveling in the travel lane L2 andthat reads the reference position information on the corresponding firsttag T1 after the article transport vehicle 4 traveling in the branchlane L2 reads the reference position information on the correspondingsecond tag T2 and before it passes through the merging location G, thenthe controller H transmits merging disallowing information (informationprovided to disallow the lane change) to the article transport vehicle 4traveling in the travel lane L1 and subsequently transmits mergingallowing information to the article transport vehicle 4 traveling in thetravel lane L1 after the article transport vehicle 4 that was travelingin the branch lane L2 has passed through the merging location G.

An article transport vehicle 4 traveling in the travel lane L1 proceedsto enter a merging location G if it does not receive merging disallowinginformation from the controller H after transmitting the referenceposition information on the corresponding first tag T1 to the controllerH. In addition, if an article transport vehicle 4 traveling in thetravel lane L1 receives merging disallowing information from thecontroller H after transmitting the reference position information on afirst tag T1 to the controller H, the article transport vehicle 4 stopsbefore it reaches the merging location G, and subsequently enters themerging location G after it receives merging allowing information fromthe controller H.

An article transport vehicle 4 traveling in the branch lane L2 proceedsto enter a merging location G if it receives merging allowinginformation from the controller H after transmitting the referenceposition information on the corresponding second tag T2 to thecontroller H. In addition, if an article transport vehicle 4 travelingin the branch lane L1 does not receive merging allowing information fromthe controller H after transmitting the reference position informationon the first tag T1 (that corresponds to a merging location) to thecontroller H, the article transport vehicle 4 stops before it reachesthe merging location G, and subsequently enters the merging location Gafter it receives merging allowing information from the controller H.

Rotating of the support members 3 while the travel control is beingperformed is described next. When causing an article transport vehicle 4to travel in a lane area LE in the travel control, if the support member(for example, first support member 3A) on or in which one or morearticles W need be placed in picking work performed in the lane area LEis located on the first side Y1 along the second direction Y of thecenter of the article transport vehicle 4, then the vehicle controller20 maintains the rotational state of the support members 3 (firstrotational state). In contrast, if the support member (for example,first support member 3A) on or in which one or more articles W need beplaced in picking work performed in the lane area LE is located on thesecond side Y2 along the second direction Y of the center of the articletransport vehicle 4, then the vehicle controller 20 changes therotational state (second rotational state) of the support members 3. Inthis case, for example, the vehicle controller 20 controls the travelmember 16 to change the orientation or relative positions of the supportmembers 3 from the second rotational state to the first rotationalstate.

A control performed to cause a plurality of article transport vehicles 4to deliver or hand over the containers C to the receiving station 7 in apreset order is described next. The controller H transmits deliveringinformation to the article transport vehicle 4 that delivers thecontainers C to the container receiving station 7 before other articletransport vehicles 4. The article transport vehicle 4 delivers thecontainers C to the container receiving station 7 when it receives thedelivering information and transmits completion information to thecontroller H when it completes delivering the containers C. When thecontroller H receives completion information from an article transportvehicle 4, the controller H transmits delivering information to anotherarticle transport vehicle 4 that delivers the containers C to thecontainer receiving station 7 next. As such, a plurality of articletransport vehicles 4 are controlled to deliver the containers C to thecontainer receiving station 7 in a preset order as a result of thecontroller H sequentially transmitting delivering information to theplurality of article transport vehicles 4.

2. Second Embodiment

The second embodiment of an article sorting facility is described nextwith reference to FIGS. 8 and 9. The second embodiment is different fromthe first embodiment in that the travel lane L1 is located to the firstside Y1 along the second direction Y of the work areas E1 so that thetravel lane L1 and the storage members 1 are located on the same sidewith respect to the work areas E1. In the description below of thearticle sorting facility in accordance with the present secondembodiment, the focus is placed on features that are different fromthose of the first embodiment described above. Features of the presentembodiment that are not specifically described below should beunderstood to be identical, or similar, to those of the firstembodiment.

The branch lane L2 is formed to be located adjacent to, and to the firstside Y1 along the second direction Y of, the travel lane L1. Thecompleted lane L3 is formed to be located adjacent to, and to the firstside Y1 along the second direction Y of, the branch lane L2. A pluralityof work areas E1 are formed to be located adjacent to, and to the secondside Y2 along the second direction Y of, the travel lane L1. A pluralityof article storage racks 2 are formed to be located adjacent to, and tothe first side Y1 along the second direction Y of, the plurality of workareas E1. The travel lane L1 and the plurality of article storage racks2 overlap as seen along the vertical direction; and the travel lane L1is located below the article storage racks 2.

The travel lane L1 in the first embodiment is so formed to extend in astraight line so that the entire travel lane L1 is located adjacent tothe branch line L2 and the work areas E1. In contrast, the travel laneL1 of the present embodiment is formed in a wave shape and is next tothe branch lane L2 and only some portions of the work areas E1 as seenalong the vertical direction Z. Note that, in the present embodiment,the second side Y2 along the second direction Y corresponds to the workside on which the work areas E1 are located with respect to the travellane L1. Note that, in the present embodiment, the travel lane L1 isformed in a wave shape in order to avoid the support frame members ofthe article storage racks 2. However, if the travel lane L1 does notinterfere with the support frame members of the article storage racks 2,the travel lane L1 may be formed to extend in a straight line along thefirst direction X and to be located to overlap with the article storageracks 2, as seen along the vertical direction Z.

3. Third Embodiment

The third embodiment of an article sorting facility is described nextwith reference to FIGS. 10 through 12. The second embodiment isdifferent from the first embodiment in that temporary storage stations31 are installed for the work areas E1. In the description below of thearticle sorting facility in accordance with the present thirdembodiment, the focus is placed on features that are different fromthose of the first embodiment described above. Features of the presentembodiment that are not specifically described below should beunderstood to be identical, or similar, to those of the firstembodiment.

As shown in FIGS. 10 and 11, at least one temporary storage station 31is provided for (to correspond to) each work area E1. In the presentembodiment, two temporary storage stations 31 are provided for each workarea E1. As shown in FIG. 12, each temporary storage station 31 includesa partial enclosure 32 configured to at least partially surround one ormore articles W, openable-and-closable members 33 which are capable ofsupporting one or more articles W placed in the partial enclosure 32,and one or more actuators (not shown) configured to operate (open andclose) the openable-and-closable member. 33. Each openable-and-closablemember 33 can be moved between a supporting position in which theopenable-and-closable member 33 extends horizontally to support the oneor more articles W, and an unsupporting position in which theopenable-and-closable member 33 extends 32 downward from the partialenclosure 32 and in which no articles W are supported thereby. Thetemporary storage station 31 is placed in a holding state for holding atleast one article W by causing each openable-and-closable member 33 tobe in the supporting position, and is placed in a removing state forremoving every article W held therein by causing eachopenable-and-closable member 33 to be in the unsupporting position. Assuch, the temporary storage station 31 is so configured that its statecan be changed between the holding state and the removing state.

As shown with chain double-dashed lines in FIG. 12, a temporary storagestation 31 is placed in the holding state when there is no articletransport vehicle 4 in the position corresponding to the temporarystorage station 31. And, as shown with solid lines in FIG. 12, thetemporary storage station 31 is placed in the removing state when anarticle transport vehicle 4 is in the position corresponding to thetemporary storage station 31. More specifically, when an articletransport vehicle 4 that is the target of picking work reaches atemporary storage station 31, removing information is transmitted to thetemporary storage station 31 from the article transport vehicle 4 or thecontroller H. The state of the temporary storage station 31 is changedfrom the holding state to the removing state to remove every article Wheld to a support member 3 on the article transport vehicle 4. Theremoved article(s) W is/are then supported by the support member 3 onthe article transport vehicle 4. And the temporary storage station 31 isplaced in the holding state after a set period of time has elapsed sinceit was placed in the removing state. Note that the state of eachtemporary storage station 31 is changed by a controller (not shown andprovided to the temporary storage station 31) that controls the one ormore actuators that operate the openable-and-closable members 33.

An indicator lamp 12 is provided for each temporary storage station 31.In the present embodiment, the indicator lamp 12 indicates the temporarystorage station 31 that is the target of picking work (i.e., in whicharticles W need to be placed in picking work). The indicator lamp 12when turned on allows the worker M to identify the temporary storagestation 31 by which an article W retrieved from a storage member 1should be supported. Thus, in the present embodiment, a worker M in awork area E1 performs picking work by retrieving one or more articles Wfrom one or more of the plurality of storage members 1 provided for thework area E1 that is assigned to the worker M and by causing eacharticle W to be supported by a temporary storage station 31 for the lanearea LE that is assigned to the worker M. As described above, one ormore articles W that were held by a temporary storage station 31 aresupported by a support member 3 on an article transport vehicle 4 whenthe article transport vehicle 4 reaches the temporary storage station31. As such, in the present embodiment, picking work is performed inwhich one or more articles W are transferred from one or more storagemembers 1 to one or more support members 3 of an article transportvehicle 4 in the travel lane L1 by using one or more temporary storagestations 31.

4. Other Embodiments

Other embodiments of an article sorting facility are described next.

(1) In the embodiment described above, an example is described in whicheach work area E1 allows, and has in operation, a worker M assignedthereto to perform picking work. However, each work area E1 may have atransfer robot (such as, one that has a robot arm with a gripper)assigned thereto which performs the picking work instead. Alternatively,there may be one or more work areas E1 in which human workers M work aswell as one or more work areas E1 in which transfer robots are placed.If both one or more work areas E1 in which human workers M work and oneor more work areas E1 in which transfer robots are placed are provided,the travel speed of an article transport vehicle 4 when traveling in alane area LE that corresponds to a work area E1 in which a human workerM works may be set to be different from the travel speed of the articletransport vehicle 4 when traveling in a lane area LE that corresponds toa work area E1 in which a transfer robot is placed.

(2) In the embodiment described above, an example is described in whichthe branch lane L2 and the completed lane L3 are provided in addition tothe travel lane L1. However, the invention is not limited to such anarrangement. For example, only the travel lane L1 may be provided.Alternatively, only one of the branch lane L2 and the completed lane L3may be provided in addition to the travel lane L1.

(3) In the embodiment described above, an example is described in whichthe travel speed of each article transport vehicle 4 under the travelcontrol can be set at any one of, and be changed from one to another of,three different speeds, namely, the first speed, the second speed, andthe third speed. However, an arrangement may be such that the travelspeed of each article transport vehicle 4 under the travel control canbe set at any one of, and be changed from one to another of, two or fouror more different speeds. In addition, the third speed only needs to bea speed that is less than the first speed, and does not have to be thespeed (i.e., zero) at which the article transport vehicle 4 is at rest.In addition, the values of the travel speeds of each article transportvehicle 4 under the travel control may be changed as desired.

(4) In the embodiment described above, an example is described in whichthe support members 3 include two support members, namely, the firstsupport member 3A and the second support member 3B. However, only onesupport member, or three or more support members may be placed on boardeach article transport vehicle 4.

(5) In the embodiment described above, an example is described in whicheach indicator lamp 12 is located between the travel lane L1 and a workarea E1. However, the location of each indicator lamp 12 may be changedas desired. For example, an indicator lamp 12 may be installed on eachof the plurality of article transport vehicles 4.

(6) In the embodiment described above, an example is described in whichthe article transport vehicle 4 is configured to be capable of rotatingthe support members 3 about an axis extending along the verticaldirection Z to the first rotational state and the second rotationalstate. However, the invention is not limited to such an arrangement. Forexample, each article transport vehicle 4 may have a turntable providedthereto which can be rotated with respect to the travel member 16 aboutan axis extending along the vertical direction Z, such that theturntable supports the support members 3. In this case, the supportmembers 3 a may be rotated to the first rotational state and the secondrotational state by rotating the turntable with respect to the travelmember 16.

(7) In the embodiment described above, an example is described in whichthe article sorting facility described is a picking facility in whichpicking work is performed to collect articles W (that were stored onstorage members 1) in or on support members 3 on the article transportvehicles 4. However, the invention is not limited to such example. Forexample, an article sorting facility may be an assorting facility inwhich assorting operations are performed to collect articles W (thatwere in or on support members 3 on the article transport vehicles 4) onstorage members 1.

(8) In the embodiment described above, an example is described in whicheach storage rack 2 is a flow rack with storage member each of which istilted downward toward its end on the second side Y2 along the seconddirection Y such that an article W that is placed on the storagemember's portion on the first side Y1 along the second direction Y wouldslide down the storage member 1 under its own weight toward and reachthe storage member's end on the second side Y2 along the seconddirection Y if unobstructed. However, the invention is not limited tosuch an arrangement. For example, one or more article storage racks 2may be regular racks in which articles W stored on the storage members 1do not move along the second direction Y.

In addition, in the embodiment described above, an example is describedin which each storage member 1 is a part or a portion of an articlestorage rack 2. However, the location of a storage member 1 does nothave to be limited to such an arrangement. For example, an outputstation to which articles W retrieved from an automated warehouse aretransported may function as a storage member 1. In addition, in theembodiment described above, an example is described in which articles Ware stored on storage members 1 with the articles W placed in storagecontainers D. However, how the articles W are stored may be changed asdesired. For example, articles W may be stored on storage members 1 withthe articles W placed on planar pallets.

(9) In the embodiment described above, an example is described in which,in the determining control, the vehicle controller 20 determines whetherthe required picking work has been completed, based on changes in theweight measured by the weighing portion 19, kind information ofarticle(s) W which is provided in the picking information and whichindicates the kind(s) of article(s) W that should be placed in andsupported by a support member 3, weight information of each article W ofeach kind indicated by the kind information, and number information forthe article(s) W (the number of the article(s) W of each kind that needto be picked) indicated by the picking information. However, how thedetermination of whether the picking work has been completed is made inthe determining control may be changed as desired. For example, anoperating portion (in the form of an operating panel, for example)including tape switches etc. may be provided near each indicator lamp12. And when a worker M completes the required picking work, the workeroperates the operating portion, which results in operation information(which indicates that the operating panel has been operated) beingtransmitted to the article transport vehicle 4. And, in the determiningcontrol, the vehicle controller 20 may determine that the requiredpicking work has been completed, when the article transport vehicle 4receives the operation information. Alternatively, or in addition, a twodimensional code, such as a 2D barcode, with information that indicatesthe kind of the article W may be displayed on the article W. Each time aworker M places an article W on a support member 3 on an articletransport vehicle 4, the worker scans the two dimensional code for thearticle W with a reader (such as a 2D barcode reader). And, in thedetermining control, the vehicle controller 20 may determine whether therequired picking work has been completed, based on kind information ofarticles W which is provided in the picking information and whichindicates the kinds of articles W that should be placed in and supportedby one or more support members 3, and number information for thearticles W indicated by the picking information, and scanned informationthat is information scanned or read by the reader.

(10) Note that any arrangement or any feature disclosed in any of theembodiments described above can also be used in combination with anyarrangement or feature disclosed in any other embodiment unlessinconsistency arises. Regarding any arrangements and features, theembodiments disclosed in the present description are provided for thepurposes of illustration only regarding all aspects. Therefore, it ispossible to make various suitable changes without departing from thespirit of the present disclosure.

5. Brief Summary of Embodiments Described Above

A brief summary of the article sorting facility described above isprovided next.

An article sorting facility comprises: a plurality of storage members,each configured to store one or more articles; a plurality of articletransport vehicles each capable of traveling in at least a portion of apreset travel lane with one or more support members on board, eachsupport member being configured to support one or more articles; aplurality of work areas each configured to allow work to be performed totransfer articles between one or more storage members and at least oneof the one or more support members on board an article transport vehiclein the travel lane, wherein each of the work areas is located adjacentto one or more storage members and to the travel lane, wherein theplurality of work areas are arranged one adjacent to another along thetravel lane, and wherein two or more article transport vehicles are inthe travel lane simultaneously to travel in a line.

With such an arrangement, articles are transported by article transportvehicles, with the articles supported by the support members, after thearticles are transferred to the article transport vehicles in the travellane. Therefore, even when, for example, an article transport vehicle towhich articles are transferred is caused to stop traveling because ofthe transfer work taking too much time in a particular work area,another article transport vehicle traveling ahead of the stopped articletransport vehicle, or another article transport vehicle travelingbehind, and with some distance from, the stopped article transportvehicle can continue traveling without stopping. Therefore, workers inother work areas can continue with their transfer work to transferarticles to the article transport vehicles. Thus, the arrangement abovehelps reduce the lowering of efficiency of transfer work in other workareas caused by transfer work taking too much time in one or more workareas. In addition, by causing any article transport vehicle, to whichall required articles have been transferred, to move out of the travellane, the ratio of the article transport vehicles in the travel lane, towhich articles need to be transferred, to the article transport vehiclesin the travel lane, to which no more articles need to be transferred,can be increased. Such an arrangement helps improve work efficiency inthe work areas.

Here, the travel lane preferably has lane areas that correspond inlocation to the work areas with each lane area corresponding to a workarea, wherein article transport vehicles preferably travel such thatthere are one or more article transport vehicles in each of the laneareas.

With such an arrangement, in each of the plurality of work areas,transfer work can be performed to transfer articles to one or morearticle transport vehicles in the corresponding lane area. This canincrease the number of work areas in which transfer work can beperformed in parallel with transfer work performed in other work areas,which helps improve the work efficiency in the work areas.

In addition, each of the plurality of article transport vehicles ispreferably capable of independently changing its travel speed.

With such an arrangement, the travel speed of each article transportvehicle can be changed suitably based, for example, on the distance toanother article transport vehicle traveling immediately ahead and on theprogress of the transfer work in an work area, etc. Thus, this featuremakes it possible to reduce any excessive distance between two articletransport vehicles, and to adjust the travel speed of an articletransport vehicle to make it easy to perform transfer work, and further,to increase the travel speed of an article transport vehicle to theextent that would not adversely affect the transfer work. This makes itpossible to improve transport efficiency of article transport vehicles,and work efficiency in the work areas.

Also, the travel lane preferably has lane areas that correspond inlocation to the work areas with each lane area corresponding to a workarea, and wherein each of the plurality of article transport vehicles ispreferably configured to travel, when traveling in a lane area: (a) at afirst speed until all required picking work, that needs to be performedin a work area that corresponds to the lane area, to transfer one ormore articles to at least one of the one or more support members onboard the article transport vehicle is completed in the work area; and(b) at a second speed, which is a higher speed than the first speed,after the required picking work to transfer the one or more articles tothe at least one of the one or more support members on board the articletransport vehicle has been completed.

With such an arrangement, each of the plurality of article transportvehicles is caused to travel: (a) at the first speed while the pickingwork to transfer one or more articles to at least one of the one or moresupport members is in progress; and (b) at a second speed, which ishigher than the first speed, after the required picking work to transferthe one or more articles to the at least one of the one or more supportmembers has been completed. Thus, such an arrangement allows the meantravel speed of the article transport vehicles in the travel lane to beincreased as a whole without making it difficult to perform transferwork to transfer articles to a moving article transport vehicle. Thismakes it possible to improve transport efficiency of article transportvehicles, and work efficiency in the work areas.

In addition, the article sorting facility preferably further comprises:a completed lane which allows an article transport vehicle to travel inparallel to an article transport vehicle that is traveling in the travellane, wherein each of the plurality of article transport vehicles ispreferably configured to be capable of changing lanes from the travellane to the completed lane.

With such an arrangement, by causing article transport vehicles forwhich all the required article transfer work has been completed tochange lanes from the travel lane to the completed lane and to keeptraveling in the completed lane, the ratio of the article transportvehicles in the travel lane, to which additional articles need to betransferred, to the article transport vehicles in the travel lane, towhich no more articles need to be transferred, can be increased, forexample. This makes it possible to improve work efficiency in the workareas.

In addition, the article sorting facility preferably further comprises:a branch lane which allows an article transport vehicle to travel inparallel to an article transport vehicle that is traveling in the travellane, wherein each of the plurality of article transport vehicles ispreferably configured to be capable of changing lanes from the travellane to the branch lane and from the branch lane to the travel lane.

With such an arrangement, it is possible to cause an article transportvehicle to travel in the branch lane instead of the travel lane whentraveling in a lane area that corresponds to a work area in which thereis no transfer work to be performed for the article transport vehicleand to cause the article transport vehicle to travel in the travel laneonly when traveling in a lane area that corresponds to a work area inwhich there is transfer work to be performed for the article transportvehicle. Thus, such an arrangement makes it possible to increase theratio of the article transport vehicles in the travel lane, to whichadditional articles need to be transferred, to the article transportvehicles in the travel lane, to which no more articles need to betransferred. This makes it possible to improve work efficiency in thework areas.

Also, the support members preferably include a first support member anda second support member, each configured to independently support one ormore articles, wherein the first support member and the second supportmember are preferably located horizontally adjacent to each other whenplaced on board an article transport vehicle, wherein, with a work sidebeing a side on which the work areas are located with respect to thetravel lane, each of the plurality of article transport vehicles ispreferably configured to be capable of rotating the support membersabout an axis extending along a vertical direction, wherein each of theplurality of article transport vehicles is preferably configured to becapable of rotating the support members, while in the travel lane, to afirst rotational state in which the first support member is located onthe work side with respect to the second support member and to a secondrotational state in which the second support member is located on thework side with respect to the first support member.

With such an arrangement, when transfer work needs to be performed totransfer articles to the first support member, the transfer work can bemade easier by placing the support members on the article transportvehicle in the first rotational state. And when transfer work needs tobe performed to transfer articles to the second support member, thetransfer work can be made easier to perform by placing the supportmembers on the article transport vehicle in the second rotational state.In other words, with such an arrangement, two support members areallowed to be provided as the one or more support members with eachsupport member configured to independently support one or more articles,while making it easier to perform transfer work to either of the twosupport members.

In addition, each of the plurality of article transport vehicles ispreferably provided with a weighing portion configured to measure theweight of one or more articles supported by at least one of the one ormore support members.

With such an arrangement, by measuring the weight of one or morearticles supported by the at least one of the one or more supportmembers with the weighing portion, it is possible to determine if the atleast one of the one or more support members supports an article, and todetermine the kind of an article based on the weight of the article ifinformation about the weight of the article can be obtained separately.

Also, a transfer area is preferably provided at a location downstream ofthe travel lane with respect to the travel direction of articletransport vehicles, wherein the transfer area preferably is an area inwhich article transport vehicles are allowed to travel without being ina line and without being required to maintain the traveling order.

With such an arrangement, because the traveling order of a plurality ofarticle transport vehicles can be changed in the transfer area, aplurality of article transport vehicles may be allowed to travel in anorder different from a specified order in the travel lane locatedupstream of this transfer area. This allows the article transportvehicles in the travel lane to have a greater degree of freedom in termsof the order in which they travel in the travel lane while making itpossible to cause the article transport vehicle to travel in thespecified order in areas downstream of the transfer area.

In addition, at least one temporary storage station is preferablyprovided for each work area, wherein each temporary storage station ispreferably configured to be capable of being placed in a holding statefor holding at least one article and in a removing state for removingevery article held therein, wherein each temporary storage station ispreferably placed in the holding state when there is no articletransport vehicle in a position corresponding to the temporary storagestation, and each temporary storage station is preferably placed in theremoving state when an article transport vehicle is in the positioncorresponding to the temporary storage station.

With such an arrangement, a temporary storage station is caused tosupport at least one article when there is no article transport vehiclein a position corresponding to the temporary storage station, and thetemporary storage station is caused to remove every article held thereinwhen an article transport vehicle is in the position corresponding tothe temporary storage station to cause the article(s) to be supported bythe one or more support members on board the article transport vehicle.This allows a worker to remove article(s), to be transferred to andsupported by an article transport vehicle, from one or more storagemembers in advance even when the article transport vehicle is not in thelane area that corresponds to the work area. Thus, such an arrangementmakes it possible to improve work efficiency in the work areas.

INDUSTRIAL APPLICABILITY

Technology in accordance with the present disclosure can be used in anarticle sorting facility which comprises a plurality of storage memberseach configured to store one or more articles, and a plurality of workareas each configured to allow work to be performed to transferarticles. **

DESCRIPTION OF REFERENCE NUMERALS AND SYMBOLS

-   -   1 Storage Member    -   3 Support Member    -   3A First Support Member    -   3B Second Support Member    -   4 Article Transport Vehicle    -   19 Weighing Portion    -   21 Temporary Storage Station    -   E1 Work area    -   E2 Transfer Area    -   L1 Travel Lane    -   L2 Branch Lane    -   L3 Completed Lane    -   LE Lane Area    -   W Article    -   Z Vertical Direction

What is claimed is:
 1. An article sorting facility comprising: aplurality of storage members, each configured to store one or morearticles; a plurality of article transport vehicles each capable oftraveling in at least a portion of a preset travel lane with one or moresupport members on board, each support member being configured tosupport one or more articles; a plurality of work areas each configuredto allow work to be performed to transfer articles between one or morestorage members and at least one of the one or more support members onboard an article transport vehicle in the travel lane; wherein each ofthe work areas is located adjacent to one or more storage members and tothe travel lane, wherein the plurality of work areas are arranged oneadjacent to another along the travel lane, and wherein two or morearticle transport vehicles are in the travel lane simultaneously totravel in a line.
 2. The article sorting facility as defined in claim 1,wherein the travel lane has lane areas that correspond in location tothe work areas with each lane area corresponding to a work area, andwherein article transport vehicles travel such that there are one ormore article transport vehicles in each of the lane areas.
 3. Thearticle sorting facility as defined in claim 1, wherein each of theplurality of article transport vehicles is capable of independentlychanging its travel speed.
 4. The article sorting facility as defined inclaim 1, wherein the travel lane has lane areas that correspond inlocation to the work areas with each lane area corresponding to a workarea, and wherein each of the plurality of article transport vehicles isconfigured to travel, when traveling in a lane area: (a) at a firstspeed until all required picking work, that needs to be performed in awork area that corresponds to the lane area, to transfer one or morearticles to at least one of the one or more support members on board thearticle transport vehicle is completed in the work area; and (b) at asecond speed, which is a higher speed than the first speed, after therequired picking work to transfer the one or more articles to the atleast one of the one or more support members on board the articletransport vehicle has been completed.
 5. The article sorting facility asdefined in claim 1, further comprising: a completed lane which allows anarticle transport vehicle to travel in parallel to an article transportvehicle that is traveling in the travel lane, and wherein each of theplurality of article transport vehicles is configured to be capable ofchanging lanes from the travel lane to the completed lane.
 6. Thearticle sorting facility as defined in claim 1, further comprising: abranch lane which allows an article transport vehicle to travel inparallel to an article transport vehicle that is traveling in the travellane, and wherein each of the plurality of article transport vehicles isconfigured to be capable of changing lanes from the travel lane to thebranch lane and from the branch lane to the travel lane.
 7. The articlesorting facility as defined in claim 1, wherein the one or more supportmembers include a first support member and a second support member, eachconfigured to independently support one or more articles, wherein thefirst support member and the second support member are locatedhorizontally adjacent to each other when placed on board an articletransport vehicle, wherein, with a work side being a side on which thework areas are located with respect to the travel lane, wherein each ofthe plurality of article transport vehicles is configured to be capableof rotating the support members about an axis extending along a verticaldirection, and wherein each of the plurality of article transportvehicles is configured to be capable of rotating the support members,while in the travel lane, to a first rotational state in which the firstsupport member is located on the work side with respect to the secondsupport member and to a second rotational state in which the secondsupport member is located on the work side with respect to the firstsupport member.
 8. The article sorting facility as defined in claim 1,wherein each of the plurality of article transport vehicles is providedwith a weighing portion configured to measure the weight of one or morearticles supported by at least one of the one or more support members.9. The article sorting facility as defined in claim 1, wherein atransfer area is provided at a location downstream of the travel lanewith respect to the travel direction of article transport vehicles, thetransfer area being an area in which article transport vehicles areallowed to travel without being in a line and without being required tomaintain the traveling order.
 10. The article sorting facility asdefined in claim 1, wherein at least one temporary storage station isprovided for each work area, wherein each temporary storage station isconfigured to be capable of being placed in a holding state for holdingat least one article and in a removing state for removing every articleheld therein, wherein each temporary storage station is placed in theholding state when there is no article transport vehicle in a positioncorresponding to the temporary storage station, and wherein eachtemporary storage station is placed in the removing state when anarticle transport vehicle is in the position corresponding to thetemporary storage station.